Rihanna alleged Thursday what many Knicks fans already suspected about J.R. Smith and his playoff woes.

In a comment on Instagram, the singer wrote that Smith is struggling because “his a** be hungover from clubbing every night during playoffs.” Smith has shot just 28.6 percent from the field since Game 5 of the first round series against the Celtics. The Knicks are down 3-1 and facing elimination heading into Game 5 of the Eastern Conference semifinals vs. the Pacers.

Rihanna outs Knicks guard J.R. Smith for partying too hard during the playoffs on her Instagram page.Before being suspended for elbowing Celtics guard Jason Terry in Game 3 of the first round, Smith was excellent, shooting 48 percent, including 4-of-9 from 3-point range. Last week, Rihanna and Smith were pictured partying at Greenhouse, a club in Manhattan.

The two were rumored to be dating last year. Rihanna appeared to be replying to someone commenting on one of her photos when she outed Smith’s hard-partying exploits.

The full text read: “f--- you and your wack a** team!! Nobody want that desert thirsty n----!! He f----- up cus his ass be hungover from clubbing every night during playoffs!!”